An organization founded back in the early days of the Tsaesci's enslavement of the humans of Higashi. Those who served the Tsaesci as Bodyguards, Spies, Assassins, and Reconnaissance Agents gained more acclaim, rapport, and reward from their Tsaesci masters. At first, the people did these jobs to live somewhat easier lives in their enslavement, but in time, there came to be a group of people who enjoyed the power that came with this service. As such, even after the fall of the Tsaesci's control, the Yakuza continued to exist as an Organized Crime Syndicate.
Masquerading as Mercenaries, Bounty Hunters, and Specialized short-term workers, the Yakuza gained a bit of a reputation and infamy in Higashi. The membership is not known, and to the main view of the social majority, the Yakuza do not still exist. The name Yakuza is not even spoken of, out of fear of secret hits being called on those who do to silence all possible revelation of the Yakuza's secrets.
The Organization of the Yakuza is divided among 5 major families that make up the majority of its membership. For the longest time, these families have held control of the whole of the organization and have the respect of its members no matter what. Beyond that, there are specialized skills taught to their members further dividing the ranks of the organization into five categories named after spirit beasts that are regarded as sources of the power those specializations bestow on the members of the Yakuza. Each family head symbolizes the power of those spirits and are often regarded as the patron of that spirit's power within the Yakuza.